Austenitic stainless steel

Abstract

An austenitic stainless steel, wherein when an amount of hydrogen emitted at a heating rate of 100° C./h and in a temperature range from 25 to 800° C. is measured by using thermal desorption analysis, an amount of emitted hydrogen [H] is less than 10.0 ppm,a peak temperature [Tp] of hydrogen emission is 350° C. or more,a peak rate [Rmax] of hydrogen emission is 0.050 ppm/min or less, anda number density of compounds having a diameter of 0.1 to 2 μm is 1.0 to 10.0/mm2.

1 . An austenitic stainless steel, wherein when an amount of hydrogen emitted at a heating rate of 100° C./h and in a temperature range from 25 to 800° C. is measured by using thermal desorption analysis,
 an amount of emitted hydrogen [H] is less than 10.0 ppm, 
 a peak temperature [Tp] of hydrogen emission is 350° C. or more, 
 a peak rate [Rmax] of hydrogen emission is 0.050 ppm/min or less, and 
 a number density of compounds having a diameter of 0.1 to 2 μm is 1.0 to 10.0/mm 2 . 
 
     
     
         2 . The austenitic stainless steel according to  claim 1 , wherein a chemical composition of the austenitic stainless steel consists of, by mass %,
 C: 0.080% or less,   Si: 1.00% or less,   Mn: 2.00% or less,   P: 0.050% or less,   S: 0.020% or less,   Cr: 17.0 to 22.0%,   Ni: 8.0 to 13.0%,   N: 0.250% or less,   Nb: 0 to 0.20%,   Ti: 0 to 0.20%,   Mo: 0 to 1.0%,   Cu: 0 to 1.0%,   Al: 0 to 0.30%,   Co: 0 to 0.50%,   V: 0 to 0.50%,   W: 0 to 0.50%,   B: 0 to 0.0050%,   Ca: 0 to 0.010%,   Mg: 0 to 0.010%,   Zr: 0 to 0.50%,   Ga: 0 to 0.05%,   Hf: 0 to 0.10%,   REM: 0 to 0.10%, and   the balance: Fe and impurities.   
     
     
         3 . The austenitic stainless steel according to  claim 1 , wherein the austenitic stainless steel is used in a high-pressure hydrogen gas environment or a liquid hydrogen environment. 
     
     
         4 . The austenitic stainless steel according to  claim 1 , wherein the austenitic stainless steel is used for a component of a hydrogen gas production apparatus or a hydrogen gas supply apparatus. 
     
     
         5 . The austenitic stainless steel according to  claim 2 , wherein the austenitic stainless steel is used in a high-pressure hydrogen gas environment or a liquid hydrogen environment. 
     
     
         6 . The austenitic stainless steel according to  claim 2 , wherein the austenitic stainless steel is used for a component of a hydrogen gas production apparatus or a hydrogen gas supply apparatus. 
     
     
         7 . The austenitic stainless steel according to  claim 1 , wherein a chemical composition of the austenitic stainless steel comprises, by mass %,
 C: 0.080% or less,   Si: 1.00% or less,   Mn: 2.00% or less,   P: 0.050% or less,   S: 0.020% or less,   Cr: 17.0 to 22.0%,   Ni: 8.0 to 13.0%,   N: 0.250% or less,   Nb: 0 to 0.20%,   Ti: 0 to 0.20%,   Mo: 0 to 1.0%,   Cu: 0 to 1.0%,   Al: 0 to 0.30%,   Co: 0 to 0.50%,   V: 0 to 0.50%,   W: 0 to 0.50%,   B: 0 to 0.0050%,   Ca: 0 to 0.010%,   Mg: 0 to 0.010%,   Zr: 0 to 0.50%,   Ga: 0 to 0.05%,   Hf: 0 to 0.10%,   REM: 0 to 0.10%, and   the balance: Fe and impurities.